This is the easiest step to charging your cell phone off of a renewable energy source. The unit is self contained and easy to use. They've been field tested everywhere from the arctic to the jungles of Africa.

The king of Brunton's Solaris line. This will easily charge most devices even in the shade. The only downside is the cost but it's well worth the money if you need the power output it provides.

This is an easy to use battery system with a built in inverter. To charge it off of a solar or wind system all you need to do is add a charge controller and charge it through the 12v port or the leads on the back. It can run smaller gadgets for more than a day and even large ones like refrigerators for a few hours.

This is a nice little wind unit. If you're in an area with a decent amount of wind it can go a long way to helping charge any battery arrays or systems you have. You need to be sure to use a battery charge controller with this unit.